Publications by authors named "Hei-wun Leung"

Honghua Oil (HHO), a traditional Chinese medicine (TCM) oil preparation, is a mixture of several plant essential oils. In this text, the extended ranges of Fourier transform mid-infrared (FT-MIR) and near infrared (FT-NIR) were recorded for 48 commercially available HHOs of different batches from nine manufacturers. The qualitative and quantitative analysis of three marker components, alpha-pinene, methyl salicylate and eugenol, in different HHO products were performed rapidly by the two vibrational spectroscopic methods, i.

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In this article, a method of using Fourier-transform infrared spectroscopy (FTIR) to identify 7 species and 3 variations of genus lycium (Gouqi) in China is described. This method is based on the additive IR absorptions of the chemical components and the differences of their relative contents in various Gouqi. These differences are reflected in the FTIR spectra.

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Article Synopsis
  • The study utilized modern extraction and high-performance thin-layer chromatography (HPTLC) to create carbohydrate profiles, or fingerprints, of different species of the medicinal mushroom Lingzhi.
  • The method involved acid hydrolysis of polysaccharides, allowing for the measurement of degradation products like mono- and oligosaccharides using HPTLC with special detection reagents.
  • Unique fingerprint patterns were identified in the monosaccharide profiles of two valuable Lingzhi species, Ganoderma applanatum and Ganoderma lucidum, showcasing the technique's potential for species differentiation.
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A rapid and non-destructive method, was used to identify seven commercial American Ginseng Tea bags by Fourier-transform infrared spectroscopy (FTIR) in this paper. It could be seen from the results, that each sample has its own characteristic infrared spectrum. Also, the seven tea bags could be divided into two groups: one is made from pure Ginseng powders, and the other is made by Ginseng extractives and additives.

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The feasibility of employing aqueous non-ionic surfactant solutions as an alternative solvent system in pressurized liquid extraction (PLE) is demonstrated for the first time using the roots of American ginseng as model solid samples. When compared to the use of pure water or methanol, the presence of a common non-ionic surfactant (Triton X-100) in water at a concentration above its critical micelle concentration was shown to enhance the amount of pharmacologically active ingredients (ginsenosides) extracted from ginseng roots. The advantages of using aqueous non-surfactant solutions were also demonstrated by comparing extraction performances between ultrasonic-assisted extraction and PLE methods.

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